a) Field of the Invention
The present invention relates to a method and apparatus for removing tree stumps from the ground, and more particularly to such a method and apparatus where a splitting attachment can be used in conjunction with conventional equipment, such as a trackhoe, in a particularly effective manner to accomplish the splitting of the stump, the removal of the stump from the ground, and also the removal of rocks and dirt from the stump.
b) Background Art
When a tract of land has been logged, quite often it becomes necessary to remove the remaining stumps. One common way of accomplishing this is to simply use a bulldozer to dig around the roots of the stump and then push the stump out. Another method is to use a trackhoe to sever the roots and the trackhoe pulls the stump out of the ground hole in one piece by use of its bucket.
A search of the U.S. Patent literature has revealed a number of devices which are used for this purpose, these are the following:
U.S. Pat. No. 4,682,638 (Becker) shows what is called a "stump extracting tool" which can be mounted to an articulated arm such as the boom of a power shovel. This tool has a vertical splitting member 1 and a laterally extending triangular plate--like member having forwardly facing stepped cutting members. The vertical member splits the stump while the laterally extending cutting member makes a horizontal cut to remove a section of the stump.
U.S. Pat. No. 4,321,761 (Hedblom) shows an apparatus for uprooting tree stumps. There is a tool 7 which is mounted to a crane. This tool 7 comprises two members 23 and 24, these members 23 and 24 are positioned adjacent to one another and then are dug into the ground to a position below the stump. Then the member 24 is raised relative to the member 23 as the member 23 presses against the ground surface beneath the stump to uproot the stump.
U.S. Pat. No. 3,842,871 (Jureiwicz) shows a tree stump cutting assembly which is mounted behind a tractor. There is a blade member 1, having a bottom cutting edge 4, a rear cutting edge 5, and a forward cutting edge 6. The blade member 1 is pivotally mounted for limited angular movement to an arm 18 that is in turn connected to a hydraulically operated mechanism which can move the blade upwardly and downwardly. The hydraulic member 23 can be used to push the blade downwardly in a splitting action, or the tractor can be moved forwardly or rearwardly to accomplish the splitting motion.
U.S. Pat. No. 3,620,271 (Loyer) shows a stump splitting blade with a cutting edge on the front and bottom, secured to the rear of a heavy tracked vehicle. There is a hydraulic ram which forces the blade into the top of the stump. The vehicle then drags the blade down and forward to cut and split the stump.
U.S. Pat. No. 2,934,108 (Bles) shows an apparatus for cutting tree stumps and roots. There is a stump splitting tool that is mounted to a boom 14. The cutting tool 22 has at its lower end a forwardly directed cutting edge 32 which makes a vertical slice into the stump, and also has a laterally extending cutting edge 42 formed along a triangular horizontal plate 44. The tool is operated to cut slices off the tree stump (as shown in FIG. 4) where the vertical edge makes a vertical slice, and the slanted horizontal cutting edge 42 cuts the slice off at the lower horizontal edge thereof.
U.S. Pat. No. 2,966,180 is also issued to Bles, and this shows a modified form of the apparatus shown in the earlier Bles patent.
U.S. Pat. No. 2,528,170 (Peacock) shows a "stump dozer". The existing blade of a bulldozer is removed, and this stump removing blade is put in its place. There is a downwardly and forwardly slanting stump extracting blade 85, and there is a vertical wedge 18 mounted to the front of the blade. The manner in which the device is used is described in this patent as follows (column 3, beginning at line 8):
"The stump is then pushed out, much in the manner that a hog roots. The blade goes down under the stump, and then as the machine pushes forward, the unit is moved up by the cable or hydraulic power unit (not shown) operating the A frame of the tractor. The stump is then left on top of the ground and is either pulled or pushed to the burning pile or loaded on a truck for sale. PA1 "Some of these stumps are so large that a dump truck cannot haul them. For this reason, I have provided the splitting wedge device mounted to the pusher, so that the stump is in smaller pieces when it has been removed from the ground. Thus, facilitating handled."